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Fastdrug delivery is very important to utilize drug moleculesthat are short-lived under physiological conditions. Techniques thatcan release model molecules under physiological conditions could playan important role to discover the pharmacokinetics of short-livedsubstances in the body. Here an experimental method is developed forthe fast release of the liposomes’ payload without a significantincrease in (local) temperatures. This goal is achieved by using shortmagnetic pulses to disrupt the lipid bilayer of liposomes loaded withmagnetic nanoparticles. The drug release has been tested by two independentassays. The first assay relies on the AC impedance measurements ofMgSO4released from the magnetic liposomes. The secondstandard release assay is based on the increase of the fluorescencesignal from 5(6)-carboxyfluorescein dye when the dye is released fromthe magneto liposomes. The efficiency of drug release ranges froma few percent to up to 40% in the case of the MgSO4. Theexperiments also indicate that the magnetic nanoparticles generateultrasound, which is assumed to have a role in the release of themodel drugs from the magneto liposomes. [ABSTRACT FROM AUTHOR]

Organicacids in the atmosphere are ubiquitous and are often correlatedwith mineral dust aerosol. Heterogeneous chemistry and the uptakeof organic acids on mineral dust particles can potentially alter theproperties of the particle. In this study, heterogeneous uptake andreaction of formic acid, HCOOH, the most abundant carboxylic acidpresent in the atmosphere, on oxide and clays of the most abundantelements, Si and Al, present in the Earth’s crust are investigatedunder dry and humid conditions. In particular, quantitative adsorptionmeasurements using a Quartz Crystal Microbalance (QCM) coupled withspectroscopic studies using Attenuated Total Reflection Fourier TransformInfrared (ATR-FTIR) spectroscopy are combined to allow for both quantificationof the amount of uptake and identification of distinct adsorbed speciesformed on silica, alumina, and kaolinite particle surfaces at 298K. These oxides and clay particles show significant differences inthe extent and speciation of adsorbed HCOOH due to inherent differencesin surface −OH group reactivity. Adsorbed water, controlledby relative humidity, can increase the irreversible uptake of formicacid. Interestingly, the resulting layer of adsorbed formate on theparticle surface decreases the particle hydrophilicity thereby decreasingthe amount of water taken up by the surface as measured by QCM. Atmosphericimplications of this study are discussed. [ABSTRACT FROM AUTHOR]